Pharmacology of autism

Abstract

The purpose of this review is to discuss the pharmacology of autistic disorder (autism) and other pervasive developmental disorders (PDDs) from the perspective of specific target symptom domains of behavior. Drug treatment strategies directed toward the following target symptom domains are included: motor hyperactivity and inattention; interfering stereotypical and repetitive behavior; aggression and self-injurious behavior (SIB); and the core social impairment of autism and other PDDs. For motor hyperactivity and inattention, studies have indicated that the α₂ adrenergic agonists, clonidine and guanfacine, are useful. A placebo-controlled study by the Research Units on Pediatric Psychopharmacology (RUPP) Autism Network found methylphenidate to be efficacious in 49% of subjects with various PDDs for these target symptoms. Preliminary data with the norepinephrine reuptake inhibitor atomoxetine are encouraging. For interfering stereotypical and repetitive behavior, controlled studies of the selective serotonin reuptake inhibitor fluvoxamine found the drug to be more efficacious and better tolerated in adults than children with autism and other PDDs. A recent controlled study of low-dose liquid fluoxetine found the drug more efficacious than placebo for interfering repetitive behavior and well tolerated. A large placebo-controlled study of the atypical antipsychotic risperidone found the drug to be efficacious for reducing aggression, SIB and tantrumming in 70% of children with autism and that the response was maintained for up to 6 months. Open-label studies of other atypical antipsychotics are generally encouraging. A small, single-blind study of the glutamatergic agent d-cycloserine showed significant benefit for the social withdrawal of autism. Future directions include studying coactive pharmacological treatment strategies utilizing more than one drug to target more than one target symptom domain in individuals with autism and other PDDs.